If anyone could prod an early exit, though, it may be Bill and Hillary Clinton, said several people in New York's political power centers who declined to be identified.

Weiner's wife, Huma Abedin, has been ex-Secretary of State Hillary Clinton's close aide for 15 years. By co-starring in her spouse's latest damage-control news conference this week, Abedin abandoned all potential claim to victim status and began to be widely viewed as Weiner's enabler.

Some news accounts even mention the former president's famous dalliances, in a reach for parallels between the two scandals.

"If the Clintons were to start to telegraph that this is an embarrassment and they don't like it, I think it's very possible he could pack it in," said another operative, allied with a Weiner rival.

The word from on high? Clinton spokesmen did not respond to requests for comment; both Clintons have let it be known for months they will stay neutral in the crowded primary race.

Whatever the private pressures, however, Weiner signed off a defiant email to supporters the other day with the message: "New Yorkers never quit, and I'll never quit on you."

Except, of course, he quit his House seat two years ago after saying he would not. First he lamely denied the sexting, then admitted to it, then said he was getting therapeutic help, then announced a "leave of absence."

After more than six weeks of this drama, he bowed to the nation's top Democrats, President Barack Obama and then-House Speaker Nancy Pelosi, and mawkishly announced his departure.

"The last time, Obama and Pelosi came out against his staying in office, but he's not beholden to them any more," said the second operative -- on a day when Pelosi, now minority leader, spoke of Weiner disrespecting women. "It's as if the only one he's beholden to politically at this point is his wife's boss."

For the moment, there are public voices against Weiner's continued pursuit of Gracie Mansion -- several editorial boards, mayoral competitors, and ex-colleague Rep. Jerrold Nadler (D-Manhattan), who said Weiner "needs serious psychiatric help."

Yet both his mentor, Sen. Charles Schumer, and Clinton's successor in the Senate, Sen. Kirsten Gillibrand, refuse to express an opinion on his candidacy. They may figure that the problem will just go away if Weiner falls short in the primary.

Weiner goes on. "When I decided to run for mayor this year," he wrote to his supporters, "I knew that the mistakes of my personal life would make things difficult for me and for my family."